Express car operation



Aug. 21, 1934. W.R. DAVIS 1,971,095

EXPRESS AR OPERATION Filed March 17, 1930 4 Sheets-Shet 1 Fig. .7.

INVENTOR William R Davis.

ATT'ORNEY Aug. 21, 1934. w. R. DAVIS EXPRESS CAR OPERATION Filed March 17, 1930 4 Sheets-Sheet 3 INVENTOR William R Davis.

ATT'ORNEY Aug. 21, 1934. w; R. DAVlS 1,911,095

EXPRESS CAR OPERATION Filed March 1'7, 1930 4 Sheets-Sheet 4 INVENTOR William RDaw's.

ATTORNEY Patented Aug. 21, 1934 EXPRESS CAR OPERATION William-R. Davis, Wilkinsburg, Pa, assignor to Westinghouse Electric & Manufacturing Company, a corporation of Pennsylvania Application March 17, 1930, Serial No. 436,406

3 Claims. (01. 187-29) My invention relates to elevator systems, and has particular relation to elevator systems in the car is operated within a local speed range in a local zone where several stops are ordinarily made and operates at a higher express speed in an express zone where the car does not stop. Such systems are advantageous in tall buildings, where separate cars serve different groups of floors; the cars for the upper floors being operated at express speed through express zones extending over several of the lower floors, the length of the express zones permitting operation at very high express speeds with only moderate acceleration and deceleration of the car.

Two systems of this type, having means for initiating operation of the car at express speed upon entry of the car into an express zone, are disclosed in the co-pending application of Frank E. Lewis, Serial No. 197,830, filed June 10, 1927 new Patent 1,793,497 Feb. 24, 1931; and Harold W. Williams, Serial No. 366,278, filed May 27, 1- 29, now Patent 1,858,283, May 17, 1932, both assigned to the Westinghouse Electric and Manufacturing Company. The systems disclosed in these applications are reliable and satisfactory and permit operation of the cars at a very high average speed. However, I have found that it is possible to increase the average car speed and hence improve the service in such systems. by providing m ans under the control of the operior initiating operations at express speed before the car reaches the express zone when traffic conditions warrant it. According to my invention, on runs the car operates at e press speed only while in the express zone, n18 on other runs the car may operate at express speed through a greater distance than the length of the express zone, thereby giving average car speed for a number of runs.

For crample, in a system in which the elevator car ordinarily operates express between the first tenth floors, and local between the tenth and twentieth floors, if on a downward trip the car should become fully loaded at the sixteenth floor, express operation may be initiated, according to my invention, shortly after leaving the sixteenth floor, so that the elapsed time for the trip will be lower than it would be if the car speed were limited to high local speed until the car reached the express zone.

Similarly, if the car serves several basements below the first floor, it may be desirable at n to initiate express operation in the upd direction before the car reaches the lower limit of the express zone.

It is, accordingly, an object of my invention to provide an elevator system in which the car is operated within a local speed range in a local zone and at express speed in an express zone and in which means under control of the operator are provided for initiating express operation of the car while the car is approaching an express zone but before the car enters the express zone.

More specifically stated, it is an object of my invention to provide an elevator system in which means are provided for starting, stopping and controlling the car within a local speed range in a local zone, and in which the car is automatically operated at express speed while in an express zone and in which meam are provided for initiating express operation'of the car be fore the car reaches an express zone, when trafiic conditions warrant it.

A. further object of my invention is to provide a system, indicated above, in which the control cicuits may be prepared to permit extended express operation in only a particular direction of car travel or may be prepared to permit extended express operation in either direction of car travel by the operation of a single manual switch.

Other objects of my invention will become evident from the following detailed description taken in conjunction with the accompanying drawings, in which I Figure 1 is a diagrammatic view of an elevator control system organized in accordance with the present invention.

Fig. 2 is an across-the-1ine diagram of the system shown in Fig. 1, with the coils and contacts of each relay assembled along vertical dotted lines for clearness.

Fig. 3 is a diagrammatic representation of the path of travel of an elevator car in connection with my invention.

Fig. 4 is a diagram similar to Fig. 2 of a modification of the system shown in Fig. 1.

Fig. 5 is a diagrammatic viewin perspective of an inductor relay of the type which I prefer to use in the practice of my invention, with parts broken away for clearness.

leierring to l of the drawings, an elevator car C is suspended by means of a cable Ca. which passes over a hoisting drum D to a suitable counterweight Cw. A direct current motor M is mounted on the shaft as the hoisting drum D. The armature M of the motor M is connected in a closed circuit with the armature G of a direct current generator G. An exciter E is mounted on the same shaft as the generator G, for supplying the direct current used in the control system. The generator G and exciter E are driven by any suitable means (not shown). Supply conductors L1 and L2 are connected to the terminal of the exciter E to be energized therefrom. The motor M is provided with a separately excited field winding MF connected to the supply conductors L1 and L2 in series with a pair of resistors 11 and 12. A pair of normally energized relays 10 and 11 are provided for short circuiting the resistors 1'1 and T2 at all times except when the motor is operating at high local speed or at express speed. A separately excited field winding G," for the generator G is arranged to be connected to the supply conductors L1 and L2 in series with resistors T3 and 14 by either of two sets of reversing switches 1 and 3 or 2 and i. A relay 5 energized from contact members of the car switch (32;, is provided for operating the set of up reversing switches 1 and 3 and a similar relay 6 energized from contact members of the car switch provided for operating the set of down reversing switches 2 and 4.

A spring-pressed electromagnetically released brake B of usual type is provided on the shaft of motor M.

An intermediate speed relay 8, controlled from contact members of the car switch Cs, is provided for short-circuiting the resistor 1'3 in the generator field circuit thus increasing the excitation of the generator G and the speed of motor M.

A pair of high local speed. relays 9 and 10 are provided for short-circuiting the resistor r l in the generator field circuit and for inserting the resistor T1 in the motor field circuit, respectively. The relay 9 is controlled from contact members of the car switch Cs. The relay 10 normally short circuits the resistor T1 in the motor field circuit, but is arranged to drop out when the relay 9 is energized and the voltage of generator G has increased to a predetermined value. A relay 13, responsive to the voltage of generator G is provided for operating the relay 1O jointly with relay 9 in the manner described above.

A set of inductor relays 1L, 2L, and SL each provided with two sets of contact members IUL, IDL; 2UL, 2DL and 3UL and BEL, respectively, are mounted on the car in co-operative relation with sets of inductor plates 1U, 1D, 2U, 2D, 3U, 31) in the hatchway. While for simplicity I have shown only a single set of inductor plates, it will be understood that one such set is provided for each local stop intermediate the upper and lower terminal floors. A set corresponding to inductor plates 1U, 2U and 3U is provided for the upper terminal floor and a set corresponding to inductor plates 11), 2D and 3D is provided for the lower terminal floor.

The inductor relays 3L, 2L and IL are arranged to interrupt holding circuits for the high local speed relay 9, the intermediate speed relay 8 and the reversing switches 1 and 3 or 2 and 4 respectively, in proper sequence to automatically stop the car, in a manner to be: hereinafter more fully described.

Each inductor relay consists of an operating coil wound on a partially complete magnetic structure, and a plurality of armatures each carrying a movable contact member in cooperative relation with a stationary contact member. Each armature comprises part of an incomplete branch of a magnetic circuit, as will be hereinafter more fully described. The contact members are normally closed and remain close after the coil. of the relay is energized, until the relay arrives at a position opposite an inductor plate (21) for example) in the. hatchway. When this occurs, the magnetic circuit for an armatiu'e of the relay is completed and the contact members (2131.1) controlled by the armature open and remain open whether the relay remains adjacent the inductor plate or moves beyond it, until the relay coil is tie-energized whereupon all of the relay contact members close.

The elevator system so far described is of the manually started, automatic landing type, with variable voltage drive and inductor landing switches, disclosed in the copending application of Edgar M. Bouton, Serial No. 731,921, filed August 14, and assigned to the Westin house Electric and Manufacturing Company.

Retur mg to 1, an express speed relay II is provided for short circuiting the resistor r2 in the motor field circuit. The relay II is normally energized to short-circuit the resistor 12 but arranged to be de-energized by the opening of contact members of an express speed inductor relay Er when the car enters an cxpress zone. When relay II is de-energized, it opens its contact members Ila, inserting the resister 12 the motor field circuit, thereby weakening the motor field and increasing the motor speed. When the car leaves the express zone, the express speed inductor relay Er closes its contact members to energize the relay II, thereby short -circuiting the resistor r2, increasthe excitation and decreasing the speed of motor M.

The energizing circuit of express speed relay II may be opened by back contact members 12a of a relay .12 when the car is not in the express Zone, to thereby initiate express operation of the car independently of the express speed inductor relay Er. The relay 12 is arranged to be energized by a momentary contact push button PB, carried on the car. The energizing circuit of relay 12 passes through contact memhere 2?) of reversing switch 2, to permit the express operation to be initiated by the push button PE in only the down direction. A knife switch Sw is provided for short circuiting the contacts 27.) of the reversing switch 2 to thereby permit extended express zone operation in either direction.

A safety switch S, carried on the car is provided for opening the reversing switch circuits in case of emergency.

A relay 14 is provided for preventing the energization of any of the inductor relays until the brake B is released, and a relay 7 is provided for preventing the energization of inductor relays lL, 2L or 3L unless the car switch Cs is centered.

The system shown in Fig. 4 comprises the same mot r control circuits as that shown in Figs. 1 and 2 but diifers from the system shown in Figs. 1 and 2 in the arrangement of the circuits of the push button and relay 12. In Fig. 4, an electromagnetically held push button switch PBS has been substituted for the momentary contact push. button PB and a relay been added for controlling the energization of the push button magnet PBM. The push button switch PBS is provided with a holding magnet PBM arranged to hold the push button contact members closed when the push button has Lil) been pushed while the magnet is energized, and to release the contact members permitting them to be opened by suitable means (not shown), such as a spring, when the magnet is deenergized. The system shown in Fig. 4 also differs from that shown in Figs. 1 and 2 in that the energizing circuit of relay 12 passes through contact members of reversing switch 1 rather than contact members of reversing switch 2, thus allowing extended express operation (Fig. i) in only the up direction, and in the omission of holding circuit contact members 12b of relay 12.

Fig. 5 shows in detail the construction of an inductor relay such as Er of Figs. 1, 2 and 4. Such a relay is disclosed in an application 01 Harold W. Williams, Serial No. 279,711 filed May 22, 1928 now Patent No. 1,858,283, and assigned to the Westinghouse Electric 8; Manufacturing Company. Referring to Fig. 5, a magnet Winding 102 is co-axially mounted on a core 126 of magnetic material, the core being fastened at its end in any suitable manner to plates 103 and 104 of magnetic material. The plate 103 is fastened by any suitable means to a base 101 of any suitable material. A plate 105 of suitable insulating material is fastened to the magnetic plates 103 and 10s by any suitable fastening means. A group of armatures 108, 108, 110 and 112 of magnetic material are separately mounted on and rotatably pinioned to the magnetic plate 104 by means of non-magnetic pins 114, and a similar group of armatures 107, 109, 111 and 113 or" magnetic material are similarly rotatably pinioned to the magnetic plate 103 by similar means (not shown). A rigid strip of insulating material 115 is fastened to each of the armatures 100 to 113 and carries at its free end a movable contact member 117, adapted to engage a stationary contact member 116 mounted by suitable means onthe plate of insulating material 105. Each pair of armatures 106, 108; 110, 112; 107, 109 and 111, 113 is joined by a tension spring 119 arranged to hold each of the contact members 117 in engagement with its respective stationary contact member 116. The movable contact members 117 of each pair of armatures 106, 108; 110, 112 etc. are bridged by a conductor 123. A transverse magnetic member 127, having depending lugs 125 is supported by brackets 129 of magnetic material fastened by suitable magnetic means such as iron screws (not shown) to the magnetic plate 104. A similar transverse magnetic member 128 is magnetically connected by similar means (not shown) to the magnetic plate 103. Each armature 106, 107, etc. carries a small magnetic member 124 which may be the supporting means for the movable contact memher 117 and which is adapted to engage a lug 125 of one of the transverse magnetic members 127 or 128 when the armature has been moved to a position to separate the contact members 117 and 116.

A magnetic shield 130 for each of the armatures 106, 107 etc. is mounted on one of the plates 103 or 104 to limit the'flux from the armatures to certain predetermined regions thereby preventing operation of the armatures except when an inductor plate occupies a definite position relative to the armature.

The operation of the above-described relay may be set forth as follows: The sets of contact members 116, 117 are normally closed by the springs 119. Each armature 106, 107 etc. is part of an incomplete branch of amagnetic circuit.

One such branch may be traced from the core 126, through the plate 103, through the armatures 111 and 113 in parallel, through a large air gap, through the armatures 110 and 112 in parallel, through the plate 104 back to the core 126. A second branch may be traced from the core 126, through the armatures 197 and 109 in parallel, thence through a large air gap, through the armatures 106 and 108 in parallel through the plate 104 back to the core 126. Passage of the relay past an inductor plate, such as 120, While the relay coil 102 is deenergized, has no eifect upon the relay armatures as there is no flux present in the relay magnetic structure. If, however, the coil 102 is energized when the relay arrives at the position shown in the drawing relative to an inductor plate, such as 120, the air gap in the branch of the magnetic circuit through armatures 106, 108, 107 and 109 is bridged by the inductor plate to a sufficient extent to cause operation of armatures 106, 108, 107 and 109 to open their respective contact members 116, 117, although there is no physical contact between the armatures and the inductor plate. Upon the operation of an armature, such as 112, the magnetic member 124 carried by the armature engages one of the lugs 125 on one of the transverse magnetic members 127 or 128 and is held magnetically by the lug until the coil 102 is deenergized, regardless of whether the relay remains adjacent to the inductor plates or moves beyond it. The armatures 106, 108 107 and 109, are, therefore, operated substantially simultaneously, opening two external circuits (the contact members controlled by two armatures being in series) when the relay arrives adjacent one inductor'plate, and the armatures 110, 112, 111 and 113 are operated substantially simultaneously, opening two other external circuits, when the relay arrives adjacent a second inductor plate, assuming that the coil 102 is energized. All of the external circuits remain open until the coil is de-energized.

The operation of the above described control system may best be understood by reference to Fig. 2, which shows the system with the elevator car at rest and the generator G and exciter E being driven by their common driving means. The motor field MF is energized through a circuit extending from line L1, through the motor field winding My, contact members 10a and 11a of relays 10 and 11 to line L2. The relay 10 is energized through a circuit extending from line L1 through back contact members 131) and 9b of relays 13 and 9' in parallel through the operating coil of relay 10 to line L2. The relay 11 is energized through circuit extending from line L1 through contact members y and x of the express speed inductor relay Em, back contact members 12a of relay 12, through the operating coil of relay 11 to line L2. Otherwise all of the control circuits are open.

Assuming that the inductor plates in the hatchway are so arranged that the car ordi- T111.

narily operates express from the first to the tenth floors and local from the tenth to the twentieth floors and the car is standing fully loaded at the sixteenth floor after a downward run from the twentieth floor, the operator may initiate further operation in the down direction by moving the handle of car switch Cs to the right until the contact segment 29 of the car switch Csbridges the contact members a and c. When this occurs, an energizing circuit for re- BE -P lays 6 and 7 is completed as follows: From supply conductor L1 through the contact members a, b and c of the car switch Cs, through the operating winding of relay 6, through the operating winding of relay 7, through the safety devices to supply conductor L2. Relays 6 and 7 operate, relay 7 opening its back contact members '70. thereby preventing energization of the inductor relays 1L, 2L and EL and relay 6 closing its contact members 6a, thereby completing an energizing circuit for the down direction switches 2 and 4. The circuit may be traced from supply conductor L1 through the safety switch 5, contact members 6:; of relay 6, interlock contact members 1] of up reversing switch 1, thence in parallel through the operating windings of reversing switches 2 and 4, through the safety devices to supply conductor L2. Down reversing switches 2 and 4 close, connecting the generator field winding G to the supply conductors L1 and L2 through the following circuit: From supply conductor Ll through contact members 2a of reversing switch 2, the generator field winding 6;, contact members 4a of reversing switch 4, through resistors 73 and 14 to supply conductor L2. Reversing switch 2 in closing also establishes a holding circuit for itself and for reversing switch 4: as follows: From supply conductor L1 through the safety switch S, contact lDL oi inductor relay 1L, contact members 2f of reversing switch 2 interlock contact members 1 of reversing switch 1, thence in parallel through the operating windings of reversing switches and a, through the safety devices to supply conductor L2. Reversing switch 2 in closing also partially completes circuits for intermediate speed relay 8 through closure of its contact members high local speed relay 9 through closure of its contact members 20; and relay 12 through closure of contact mem ers 2b.

Reversing switch 4 in closing completes a circuit for the release coil of brake B and the operating coil of relay 14. This circuit may be traced from supply conductor Ll through the release coil 01": bralre B, contact members 4b of reve'sing switch 4, the operating coil of relay 14 to supply conductor L2. Relay 14 closes, closing its contact members 14c thereby completing the circuit of the operating coil of express inductor relay Er and preparing the circuits of the operating coils of inductor relays 1L, 2L and BL for subsequent closure in response to the dropping out of relay 7. The circuit of the operating coil of express speed inductor relay Er extends from supply conductor Ll through contact members I g," of the inductor relay Er, in parallel, thence returning through the operating coil of inductor relay through conductor 16, contact members 14a of relay 14, to supply conductor L2. Energization of the coil inductor relay Er has no immediate effect on the relay armatures and con tact members as the magnetic circuit of the relay is still incomplete.

The generator G now generates a low voltage, the brake B is released and the car moves downward at slow speed.

If the handle of car switch Cs is moved further to the right, contact segment I) of the car switch bridges contact members a and [1, thereby completing an energizing circuit for intermediate speed relay 8. This circuit extends from supply conductor L1 through contact members a, b and d of the car switch Cs, contact members 2DL of inductor relay 2L, contact members 20! of reversing switch 2, the operating winding of relay 8, through the safety devices to supply conductor L2.

Relay 8 closes, short circuiting resistor r3 by closure of its contact members 8a; opening its contact members in the de-energized circuit of the inductor relay 1L; and establishing a holding circuit for itself through closure of its contact members 8b. This holding circuit extends from supply conductor L1 through conductor 15, contact members 8b of relay 8, contact members 2DL of inductor relay 2L, contact mabers 2d of reversing switch 2, the operating coil of relay 8, through the safety devices to supply conductor L2.

The generator G now generates an intermediate voltage and the car moves downward at intermediate speed.

If the handle of car switch C8 is moved further to the ri ht, contact segment I) of the car switch bridges the contact members a and e thereby completing an energizing circuit for high local speed relay 9. This circuit extends from supply conductor 1.1 through contact members a, b and e of the car switch Cs, through contact members 3DL of inductor relay 3L, contact members 20 of reversing switch 2, the operating coil of relay theme through the safety devices to supply conductor L2.

Relay 9 closes, short circuiting the resistor r l through closure of its contact members 9a; preparing the energizing circuit of relay 10 for subsequent control by relay 13 by the opening of its contact members 9b; opening its contact members lid in the de-energized circuit of inductor relay 2L, and completing a holding circuit for its-ll? by closure of its contact members 90. This helping circuit extends from supply conductor Ll, through conductor 15, contact members of relay 9, contact members BDL of inductor relay 3L, contact members 20 of reversing switch 2, the operating coil of relay 9, thence through the safety devices to supply conductor L2.

The generator voltage builds up, being delayed somewhat by the time constant of the generator field, until it reaches a value suificient to operate the relay 13. When this occurs, the relay 13 opens its contact members 13c, thereby breaking the energizing circuit of relay 10. Relay 10 drops out inserting resistor T1 in the circuit of motor field Mf, weakening the motor field and causing the motor speed to increase.

The generator is now generating its maximum voltage, the motor excitation is at its intermediate value and the car is at some point between the sixteenth and tenth floors, moving downward at high local speed.

The operator now has the option of permitting the car to continue at high local speed until the car reaches the express zone, when express speed will be automatically initiated, or of at once initiating express operation by pushing the push button PB.

Let us first assume that the operator does not push the button PB. The car continues to move downward at high local speed until the express inductor relay Ex arrives at a position opposite the inductor plate Y in the hatchway. When this occurs, a branch of the magnetic circuit in the inductor relay Ea: is completed and the contact members 3 and y of the inductor relay open. The opening of contact members y 01 the relay breaks the circuit of relay 11. Relay 11 drops out, inserting the resistor 12 in the circuit of the motor field winding Mf, decreasing the motor excitation and increasing the motor speed.

The generator is now generating its maximum voltage, the motor excitation is at its minimum value and the car isat some point in the express zone moving downward at maximum or express speed.

Let us now assume that instead of permitting the car to continue downward at high local speed after leaving the sixteenth floor, the operator had pushed the push button PB. Closure of the push button ,conltact members completes an energizing circuit for the coil of relay 12 which may be traced as follows: From supply conductor L1, through contact members at and y of the express speed inductor relay Er, contact members 2b of reversing switch 2, contact members of the push button PB, the operating coil of relay 12, contact members 101) of relay 10 through contact members 14a of relay 14 to supply conductor L2.

Relay l2 closes, breaking the circuit of relay 11 by the opening of its contact members 120,, establishing a holding circuit for itself by closure of its contact members 12b in shunt to the push button PB, and opening its contact members 120 in the circuit of the operating coils of inductor relays 1L, 2L and EL. Relay 11 drops out inserting the resistor 12 in the circuit of the motor field M).

The car now rapidly accelerates to express speed without change in the control circuits until the inductor relay Er arrives adjacent the inductor plate Y somewhat below the tenth floor. When this occurs, the contact members y and y of the inductor relay open but have no effect on the control circuits as the energizing circuit of relay ll is already open and the circuit of relay 12 is held through the closed contact members :c of the inductor relay Er, which contact members are connected in parallel to the contact members y.

From this point on the operation is the same whether express operation has been initiated by the push button PE or the inductor plate Y. The car continues downward at express speed until the express speed inductor relay Ea: arrives at a position adjacent the inductor plate X at the lower limit of the express zone. When this occurs, the air gap in the second branch of the relay magnetic circuit is bridged and the contact members as and m of the relay open. The contact members x, 112', y and y of the inductor relay are now all open for an. instant but are immediately reclosed as will be explained hereinafter. The opening of contact members at breaks the circuit of relay 12 and the energizing circuit for the coil of inductor relay Er. Relay 12 opens breaking its own holding circuit by the opening of its contact members 1219; preparing the energizing circuit of relay 11 for subsequent control by inductor relay Eco by closure of its contact members 12a; and preparing the energizing circuit of inductor relays 1L, 2L and 3L for subsequent control by relay 7 by the closure of its contact members 120. Opening of the energizing circuit of express speed inductor relay Ea: releases all of the express relay armatures permitting contact members ca, .73, y and y to reclose. Closure of contact members 1] and x completes the energizing circuit of relay 11. Relay 11 closes short circuiting the resistor r2, thereby increasing the excitation and decreasingthe speed of motor M.

Closure of contact members a: and y re-establishes the energizing circuit for the inductor relay Ex, but as the relay E1: is now past the inductor plate X, no further operation of the relay contact members takes place.

The car is now between the lower limit of the express zone and the first floor, moving down ward at high local speed. The switch Cs may now be centered, if it has not already been centered. Centering of the car switch has no effect on the motor after express operation has been established until the car approaches the next local stop the express zone. In the present case, the next local step would be the first iioor. Centering oi the car switch Cs breaks the closing circuit or high local speed relay 9 at contact member 6; breaks the closing circuit of intermediate speed 8 at contact member (1; and breaks the circuit of relays 6 and '7 at contact member 0. Relays 8 and 9, however, are held in by their holding circuits traced above. Relay 6 drops out, breaking the closing circuit of down reversing switches 2 and 4 at its contact members do. Reversing switches 2 and 4, however, are held in by their common holding circuit traced above. Relay 7 drops out, establishing an energizing circuit for inductor relay 3L. This circuit extends from supply conductor L1, through the energizing coil of inductor relay 3L, contact members 120 of relay 12, contact members 7a of relay 7, thence through contact members 14a of relay is to supply conductor L2.

The contact members of inductor relay 3L remain closed after the inductor relay coil is energized until the inductor relay arrives at a position adjacent inductor plate 31) for the first floor. When this occurs, the contact members 3DL of inductor relay 3L opens, breaking the holding circuit of high local speed relay 9. Relay 9 drops out, inserting resistor rd in the generator field circuit by the opening of its contact members 9a; reestablishing the circuit of relay 10 by closurerof its contact members 92); breaking its own holding circuit by the opening of its contact members 90; and establishing an energizing circuit for inductor relay 2L by the closure of its contact members 9d. This circuit extends from. supply conductor L1, through the operating coil or" inductor relay 2L, contact members 9d of high, local speed relay 9, contact members 12c of relay 12, contact members 7a of relay 7, thence through contact members 14a of relay 14 to supply conductor L2. Relay it closes, short circuiting the resistor 11 in the motor field circuit by closure of its contact members 10a, and opening its contact members 101) in the deenergized circuit of relay 12.

The speed of the car now decreases to. intermediate speed and the car continues downward until inductor relay 2L arrives at a position adjacent the inductor plate 21). When this occurs, contact members 2DL oi inductor relay 2L open, breaking the holding circuit of intermediate speed relay 8. Relay 8 drops out, inserting the resistor T3 in the generator field circuit by the opening of its contact members 8a; breaking its own holding circuit by the opening or its contact members 812; and establishing an energizing circuit for inductor relay 1L by closure of its contact members 80. This circuit may be traced from supply conductor L1, through the operating coil of inductor relay 1L, contact members of intermediate speed relay 8, contact members 120 of relay 12, contact members 7a of relay 7,

thence through contact members 14a of relay 14 to supply conductor L2.

The speed of the car now decreases to low speed and the car continues downward until inductor relay 1L arrives at a position adjacent the inductor plate 1D. When this occurs, contact members lDL of inductor relay 1L open, breaking the common holding circuit or reversing switches 2 and 4. Reversing switches 2 and 4 drop out. Reversing switch 4 in dropping out breaks the common circuit of the 1' relay is and the release coil of the brake B, by the opening of its contact members 4?); and breaks the generator field circuit by the opening of its contact members 4a. The brake is applied and relay 14 drops out. Relay 14 in dropping out breaks the circuits of inductor relays 1L, 2L and BL by the opening of its contact members 14a. Inductor relays 1L, 2L and EL are ole-energized, closing their contact members in preparation for fur ther operation. Reversing switch 2 in dropping out opens its contact members 2a, 2b, 2c, 2d and 2f and closes its interlock contact members 2c. The opening of contact members 2a breaks generator field circuit, the operation of the remaining contact members having no efiect as the control circuits passing through them are all open at other points.

The car is now standing at the first fioor, the motor field is energized, relays 10 and 11 are energized, reversing switches 1, 2, 3 and 4 interlock relays 5 and 6, relay 7, accelerating relays S and 9, inductor relays 1L, 2L, 3L and E51: and relays 12, 13 and 14 are all de-energized and the car switch Cs is centered in preparation for further operation by actuation of the car switch Cs.

Operation in the up direction will be readily understood from the above description of operation in the down direction.

The operation of the system shown in Fig. 4 is identical with that of the system shown in Figs. 1 and 2 except that the circuits for extended express operation may be prepared while the car is at rest by pressing the push button switch PBS, without waiting until the car accelerates to high local speed, as is necessary in the system shown in Figs. 1 and 2. The system shown in Fig. 4 is also arranged to permit extended express operation in only the up direction when the switch Sw is open or in both directions when the switch Sw is closed. Referring to Fig. 4, additional contact members and 4c are provided on the reversing switches 3 and 4 and additional contact members 915 are provided on the high local speed relay 9 for controlling the energization of an additional relay 55. Additional contact members 8d are provided on the intermediate speed relay 8 for controlling the circuit of the push button magnet PBM.

The operation is as follows: The push button magnet PBM is energized while the car is at rest through a circuit extending from supply conductor L1, through contact members a: and y of express-speed inductor relay Eat in parallel, through the push button magnet PBM, back contact members 5512 of relay to supply conductor L2. If the push button switch PBS is pressed while the car is at rest, its contact members are, therefore, held closed by the push button magnet PBM. Closure of the push button switch PBS while the car is at rest has no immediate effect on the control circuits, as the energizing circuit of relay 12 is open at contact members 10?).

If the car switch Cs is now moved to start the car in the up direction and accelerate it to high local speed in the manner previously described, the following additional operations occur in the system shown in Fig. 4, during the accelerating operation. Upon the closure or intermediate speed relay 8, a circuit for the push button magnet PBM, independent of relay 55 is established as follows: From supply conductor L1, contact members a: and y of express speed inductor relay E0: in parallel, through the push button magnet Winding PBM, contact members 8d of intermediate speed relay 8 to supply conductor L2. Upon the closure of high local speed relay 9, a circuit for relay 55 is established as follows: From suppiy conductor Ll, through contact members 30 of reversing switch 3, the operating coil of relay 55, contact members 96 of high local speed relay 9 to supply conductor L2. Relay 55 closes, opening its contact members 55b and closing its contact members 55a. The opening of contact members 551) has no immediate effect on the circuit of push button magnet PBM as this circuit is held through contact members 8d. The closing of contact members 55a establishes a holding circuit for relay 55 in parallel to contact members 96.

As the generator voltage builds up, relay 13 operates, causing high local speed relay 10 to drop out in the manner previously described. Upon the dropping out of high local speed relay 10, circuit for the operating coil of relay 12 is established as follows: From supply conductor Ll through contact members .r and 3 of express speed inductor relay E2: in parallel, thence through contact members lb of reversing switch 1, through the push button contact members PBS, through the operating coil of relay 12, com tact members 101) of relay 10 to supply conductor L2. Relay 12 closes, opening the cir cuit of express speed relay 11 at contact members 12c. Express speed relay 11 drops out, inserting resistor T2 in the motor field circuit, weakening the motor field and increasing the motor speed to express speed value.

The car continues upward at express speed into the express zone. Upon entry of the car into the express zone, contact members a: and it of the express speed inductor relay Ea: open, but have no effect on the control circuits, as the contact members 11' in parallel to contact members 3: remain closed, and as the circuit through contact members a," is already open at contact members 12a of relay 12.

When the car reaches the upper limit of the express zone, the contact members y and y 01'. express speed inductor relay Em open for an instant, and thereafter all of express speed contact members an, x, y and y reclose in the manner previously described. Upon the opening of contact members as, the push button magnet f PBM is momentarily deenergized, and the push button contact members PBS open. The opening of the push button contact members PBS breaks the circuit of relay l2. Relay 12 drops out. Upon the reclosure of contact members 1/ and as, an energizing circuit for relay 11 is completed from supply conductor L1, through contact members y and x of express speed inductor relay Ex, contact members 12a of relay 12, the operating coil of relay 11 to supply conductor L2. Relay 11 closes, short circuiting resistor r2, increasing the excitation oi motor M and decreasing the speed of the car to high local speed.

The further slow down and stop operations may be initiated for any selected floor by centering of the car switch in the manner previously described. Upon the opening of reversing switch 4 when the car stops, the circuit of relay is broken at contact members do. Relay 55 drops out, completing the circuit of push button magnet PBM by closure of its contact members 55%;. Upon stopping of the car the remaining circuits are prepared for further operation in either direction in the manner previously described.

It will be understood that the above described embodiments of my invention are illustrative only and that various elements such as limit switches, door and gate interlocks, etc. which would in practice he used have been omitted for simplicity.

I do not wish to be restricted to the specific structural details, arrangement of parts or circuit connections herein set forth, as various modifications thereof may be effected without departing from the spirit and scope of my invention. I desire, therefore, that only such limitations shal be imposed as are indicated in the appended claims.

I claim as my invention:

1. In an elevator system, an elevator car operable through a local zone and an express zone; motive means for said car; speed-limiting means for said motive means; manual means for rendering s seal-limiting means ineffective when said car is in said local zone and is approaching said express zone; means responsive to the p sition of said car for rendering said speeddimiting means ineffective when said car enters said express zone; and means for preventing said manual means irom rendering said speed-limiting means ineffective when said car is in said local zone and is moving away from said express zone.

2. In an elevator system, a car operable through a first zone and a second zone, driving means for said car, means for controlling said driving means to move said car in a first direction, a second means for controlling said driving means to move said car in a second direction, auxiliary means for causing said driving means to operate at a predetermined speed, autcmatic means responsive to the position of said car for initiating operation 01" said auxiliary means upon entry or" said car into said second zone, a manual control, and means responsive to said second means and said manual control for initiating operation of said auxiliary means independently of said automatic means.

In an elevator system, a car operable through a first zone and a second zone, driving means for said car, means for controlling said driving means to move said car in a first direction, a second means for controlling said driving means to move said car in a second direction, auxiliary means for causing said driving means to operate at a predetermined speed, automatic means responsive to the position of said car for initiating operation of said auxiliary means upon entry of said car into said second zone, a manual control, m ans responsive to said second means and said manual control for initiating operation of said auxiliary means independently of said automatic means, and means for rendering said last mentioned means responsive to said manual control independently of said second means.

WILLIAM R. DAVIS. 

